Even Greener Pastures

And you're using our "prdel" to refer to jail? "Idź do pierdla"? We use the German Loch (hole) for jail but it's not rude, just colloquial. I wonder what Germans use? A French word?

The most commonly used informal word for Gefängnis (prison) is Knast. There's also an exact equivalent to "behind bars": hinter Gittern. The expression schwedische Gardinen (Swedish curtains) isn't much used anymore, it's from 1906, apparently, and refers to the high quality of Swedish iron products (I'd had no idea!).
The colloquial verb for sending someone to prison is verknacken, that's why (Ex-)Knacki means "jailbird".

And the best one comes from Trautenberk, a character from an old kids' series. They never admitted he was German, they just hinted. He curses "Himmel-Herrgott-Donner-Wetter-Kruncajs-Element!"

Ah! Oh yes, there's "Himmel, Arsch und Zwirn!" (heavens, ass and yarn) or "Himmel, Arsch und Wolkenbruch!" (... and, er, sudden rain) if you're feeling particularly vexed.

"Donnerwetter!" (literally: thunder-weather), "Donnerkeil!" (literally: thunder-wedge*) and "Donnerlittchen!" are all used to show you're impressed.
*wiktionary gives "thunderbolt" as the English meaning, which is a bit misleading since we only say Donner when we're talking about a storm.

A relatively new expression (ca. 2000) for astonishment I quite like is Holla die Waldfee (... the wood fairy), also used ironically.